TABLE 2.

MIC₅₀s, MIC₉₀s, MIC ranges, and percentages of susceptibility for beta-lactams, carbapenems, quinolones, and chloramphenicol for 4,208 enterococci of which 846 were HLR

Bacterial species (n) and drug	MIC (μg/ml)			% Susceptiblea
	Range	50%	90%
E. faecalis (2,804)
Amoxicillin	0.03–≥32	0.5	0.5	99 (≤8)
Cefpirome	0.03–≥256	8	16	70 (≤8)
Imipenem	0.03–256	1	2	99
Meropenem	0.03–256	4	8	97 (≤8)
Chloramphenicol	0.25–64	4	32	75
Ciprofloxacin	0.12–64	0.5	1	94
Sparfloxacin	0.03–64	0.25	0.5	94 (≤2)
Trovafloxacin	0.03–16	0.12	0.25	94 (≤2)
Moxifloxacin	0.03–16	0.12	0.25	94 (≤2)
E. faecalis with HLR to gentamicin (689)
Amoxicillin	0.03–≥32	0.5	1	99
Cefpirome	0.12–≥256	32	≥256	17
Imipenem	0.03–128	2	4	99
Meropenem	0.03–256	8	16	63
Chloramphenicol	1–64	8	32	43
Ciprofloxacin	0.12–64	16	64	21
Sparfloxacin	0.03–64	16	32	23
Trovafloxacin	0.03–16	4	8	31
Moxifloxacin	0.03–32	4	8	28
E. faecium (440)
Amoxicillin	0.03–64	4	32	60
Cefpirome	0.12–≥256	≥256	≥256	16
Imipenem	0.03–≥256	16	128	41
Meropenem	0.12–≥256	64	≥256	24
Chloramphenicol	0.5–64	4	8	74
Ciprofloxacin	0.12–64	2	64	67
Sparfloxacin	0.03–64	0.5	16	78
Trovafloxacin	0.03–16	1	8	83
Moxifloxacin	0.03–64	1	8	84
E. faecium with HLR to gentamicin (134)
Amoxicillin	0.03–256	32	64	15
Cefpirome	0.03–≥256	≥256	≥256	1
Imipenem	0.03–≥256	128	≥256	6
Meropenem	0.03–≥256	≥256	≥256	3
Chloramphenicol	0.12–32	4	16	56
Ciprofloxacin	0.25–≥64	4	≥64	48
Sparfloxacin	0.12–≥64	1	32	55
Trovafloxacin	0.12–16	2	8	57
Moxifloxacin	0.25–32	2	8	58
Other species (118)
Amoxicillin	0.03–64	0.25	2	92
Cefpirome	0.03–≥256	32	≥256	37
Imipenem	0.03–256	1	16	89
Meropenem	0.03–256	4	32	73
Chloramphenicol	1–64	4	8	88
Ciprofloxacin	0.03–≥64	0.5	4	89
Sparfloxacin	0.03–32	0.5	2	92
Trovafloxacin	0.03–8	0.12	2	94
Moxifloxacin	0.03–16	0.12	2	91
Other species with HLR to gentamicin (23)
Amoxicillin	0.25–64	32	64	35
Cefpirome	2–≥256	≥256	≥256	7
Imipenem	0.5–≥256	128	≥256	26
Meropenem	2–≥256	≥256	≥256	17
Chloramphenicol	2–32	16	32	26
Ciprofloxacin	0.5–32	1	16	83
Sparfloxacin	0.12–32	0.5	8	87
Trovafloxacin	0.03–8	0.5	4	87
Moxifloxacin	0.12–8	1	4	87

^aCriteria are those published by the NCCLS. The MIC breakpoints chosen if no criteria were given by the NCCLS were those of the class representatives (ampicillin for amoxicillin and cefpirome, imipenem for meropenem, and ciprofloxacin for sparfloxacin, trovafloxacin, and moxifloxacin) and are given in parentheses.